The effect of gestational age on intralipid tolerance in newborn infants.

Tolerance to intravenously administered Intralipid was studied in 18 newborn infants aged 4 to 8 days and gestation 27 to 40 weeks. Clearance of a bolus injection of Intralipid from plasma was an exponential function following first order kinetics. Less mature infants had a clearance rate less than half that seen in more mature infants. Free fatty acids rose more rapidly and were maintained above fasting levels throughout the study in the immature group, probably because of impaired utilization of free fatty acid. The slower clearance of Intralipid in immature infants may be related to lipoprotein lipase deficiency secondary to their limited adipose tissue mass.